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ClRCULAH   N 


I  oitecl  Slates  Department  <> 

BUREAU  OK  KNTOM 
L.  O.  IIOWAkl).   l 


I  III     kPPl  I     I  IOGOT  OK    •  KM 
i  Bhagoli  lis    |  /  >  ypi  hi  |   pumom 

B]      A.     I..     Ql     \1  N  I   \N'   I  . 

Iii  Chargi   "f  Deciduous  Fruit  Insect  Investigations. 

Five  important   insect   pests  injure  the  fruit  of  1 1 » * ■  apple  in  tin' 

United  States,  namely,  the  codling  moth  i  <  'arpocapsa  i><>nm„,  II,'  I .. . . 

the  lesser  apple  worm  I  Enarmonia  prunieora  Walsh),  the  plum  cur- 

culio  (C ' onotrachelua  nenuphar  Hbst.),  the  apple  curculio   (Antho- 

uadrigibbus  Say),  and  the  species   under  consideration. 


h 

i'ir.    |.-    ipp)e  maggot    ■  /.•'■••■■  larva  or  maggot;  <■.  tunnel 

'I.   puparlum  :    •  .    .  g    injury    by    m  I 

d  ;  c,  still  more  enlarged  ;  • .  reduced,     i  Original.  I 

The  apple  maggot,  as  the  name  implies,  is  the  larva  of  a  fly  or 
dipterous  insect,  and  belongs  to  the  family  Trypetidae,  which  group 
contains  numerous  other  fruit-infesting  maggots,"  some  of  them  very 
serious  pests,  and,  from  their  structure,  mode  of  life,  and   feeding 

habits,  very  difficult   of  control.     Apple-   injured   or  "  railroaded  " 
by  the  apple  maggot  show  discolored  winding  burrows,  or  track-,  and 

■  Inastrcpha  i  Trypeta)  ludens  Loew.,  the  so-called  Mexican  orange  worm,  is 
an  enemy  of  oranges  In  portions  of  Mexico,  Infesting  also  the  gnava  and  mango, 
and  .1.  ocidusa  Walk,  infests  the  peacb  in  the  same  country.  Rhagoletis 
ribicola  Doane  infests  currants  and  gooseberries  In  the  United  states,  as  does 
also  Epochra  canadensis  Loew.  /.'.  cingulata  Loew  has  recently  been  found  to 
1h-  a  cherry  pest  lu  this  country,  working  In  a~Tnry-^ntHku^_iii_jJie_Knro|>ean 
cherry  rlv.  Trypeta  etrasi  L.  (signata  Meig.>.  Vemiltts.  capitat  fEe 

878     No.  101— OG 


cavities. herd  and  there  in  the  flesh,  and  when  infested  with  several 
Larvae  the  pulp  will  be  usually  quite  honeycombed  with  their  burrows 
and  more  or  less  broken  down  into  a  yellowish  mass,  merely  held 
together  by  the  skin.     (See  fig.  1,  c.) 

DISTRIBUTION    AM)   DE8TRTJCTIVENESS. 

The  apple  maggot  is  a  native  American  specie.-,  its  natural  food 
being  haws  (Crataegus),  and  in  at  least  one  instance  it  has  been  bred 
from  crab-apples.  Its  feeding  upon  cultivated  apple.-  is  thus  an  ac- 
quired habit,  and  although  the  insect  has  been  reported  from  widely 
separated  points  in  the  central  and  eastern  State.-,  indicating  its  pos- 
sible general  distribution,  for  some  reason  it  does  not  attack  the  apple 
throughout  its  range,  but  only  in  certain  localities  and  portions  of  the 
country.  This  circumstance  is  a  fortunate  one  for  the  apple  grower, 
and  from  a  scientific  standpoint  is  of  much  interest.  Walsh  thought 
it  might  be  explained  on  the  supposition  of  the  development  in  the 
New  England  States,  where  its  injuries  to  apples  were  first  noticed. 
of  a  race  of  apple-infesting  individuals,  the  descendants  of  which, 
with  the  acquired  habit,  have  been  gradually  distributed  to  other 
localities. 

The  apple  maggot  was  described  by  Walsh  in  the  American  Jour- 
nal of  Horticulture  for  December,  1867,  pages  338-343,  and  also  in 
the  First  Report  of  the  Acting  State  Entomologist  of  Illinois,  from 
flies  from  eastern  apples  and  from  Illinois  haw.-.  Adult  specimens 
from  this  latter  fruit  had  been  secured  by  him  some  five  or  six  years 
earlier,  and  in  July,  1867,  he  reared  Mies  from  maggots  infesting  ap- 
ples from  Connecticut,  Massachusetts,  and  New  York,  and  conclu- 
.sively  showed  the  identity  of  the  insects  infesting  haw-  in  Illinois 
with  those  infesting  apples  in  the  northeastern  part  of  the  United 
States.  In  the  New  England  States  mentioned,  however,  the  species 
had  been  noted  as  an  enemy  of  apple  for  some  years  before  the  time 
of  AValsh's  description.  By  1866  it  was  common  in  the  Hudson  River 
country,  at  North  Hempstead,  Eong  Island,  in  the  Oneida  commu- 
nity in  New  York  State,  at  East  Falmouth.  Mass.,  ami  probably  in 
Vermont,  and  it  occurred  in  Connecticut." 


called  Mediterranean  fruit  fly,  or  Bermuda  peach  maggot,  is  widely  distributed. 
Infesting  a  considerable  variety  of  soft  fruits,  as  oranges,  peaches,  plums. 
pineapples,  and  bananas,  but  fortunately  lias  not  yet  been  introduced  into  the 
United  States.  In  Europe  Tephritis  onoperdinis  Fab.  injures  celery,  and  T. 
tryoni  Froggatt  seriously  infests,  in  portions  of  Australia,  bananas,  peaches. 
oranges,  etc.,  and  another  species  of  this  genus  {psidi  Froggatt)  in  that  country 
infests  guaras.  Trypeta  musce  Froggatt  seriously  injures  bananas  in  the  New 
Hebrides.  Some  Of  these  species  are  very  general  feeders,  and  the  greatest 
care  should  be  exercised,  especially  in  the  case  of  the  Bermuda  peach  maggot, 
that  they  be  not  introduced  into  the  United  States. 

"First  Kept.  Acting  State  Ent.  Illinois,  pp.  •JU-.V.l   (1St;7). 
[Cir.  101  ] 


I,,   L881  the  apple  maggol  was  reported  by  Professor  Comstock 
from  Ethaca.  N.  V.,  in  apples,  and  was  bred  bj  him  from  (  r 
Bj   Washington,  D.  I  ,     Profe  *>rCook,<  in  1884,  received  specimen* 
from  Delavan,  Wis,,  where  it  was  reported  as  doing  verj  great  in- 
jury, and  the  year  follow  ing,  the  inseci  was  the  cause  ol  considerable 
i  in  [ngham  and  adjoining  counties  in  Michigan. 

,„,     in  L88  the  additional  localities  of  North  Ashburn 

ham,  Mass.,  Franklin  and  Schenectady,  N.  V.,  and  Brandon,  V*t.    [1 

introduction  into  Mail  bated  bj    Professor  Harvey,    urred 

prior  to  L882,  bj  which  time  it  had  become  well  established,  and  bj 
1899  occurred  quite  generally  over  the  State,  [ts  occurrence  al  Mont- 
dair  N.  J.,  was  recorded  in  L889  by  Mr.  E.  Williams,  in  Garden 
and  Forest,  page  527,  and  this  locality  is  also  given  for  the  apple 
maggol  by  Dr.  J.  B.  Smith  in  his  list  of  insects  of  New  Jersey,  page 

687  I  L899).  . 

In  1894  Doctor  Howard  '  records  the  occurrence  ol  the  apple  mag- 
got from  Waynesville,  N.  C.,and  Doctor  Fletcher    records  its  Erst  ap- 
pearance in  Canada, Augusl  31,1896,in  apples  from  Adolphustown, 
Ontario.     As  stated  by  Professor  Lochhead,"  it  had  become  quite  in- 
jurious by  1902,  more  than  one-half  of  the  crop  having  been  destroyed 
in  some  orchards  in  Prince  Edward  County.     Professor  Osbora,' 
,n  the  authority  of  Professor  Hine,  records  its  occurrence  in  uorth- 
western  Ohio  in  L904,  and  states  that  injured  fruit  comes  on  the  mar- 
ket al  Columbus,  though  perhaps  from  outside  of  the  Stair.     Doctor 
Chittenden    notes  that  the  apple  maggol  was  unusually  injurious  in 
Ohio  in  L903.     By  L905  the  insect  had  extended  it-  range  in  C  anada, 
as  shown  by  the  records  of  Doctor  Fletcher     of  its  occurrence  al 
Como  and  St.  Hilaire,  Quebec    The  apple  maggol  is  recorded  from 
Minnesota  by  Professor  Washburn,1  and  the  records  ol  the  Bureau  ol 
Entomology  show   the  additional   localities  of   Dyberry,   Pa,,  and 

Douglas,  Mich. 

Numerous  records  of  this  Bureau,  as  well  as  published  accounts, 
show  that  the  insed  is  generally  distributed  throughout  the  greater 
pari  of  the  New  England  States,  and  thai  il  is  a  very  destructive 

Kept.  Ent.  I  .  S.  Dept  Agric,  1881-82,  p.  198. 
Rept.  Mich.  Hort  8<x  .,  isst.  p.  200. 

ond  Report  N.  Y.  State  Ent,  p.  121    (1886). 
Ann.  Rept.  Maine  State  Coll.  Agr.  Exp.  Sta.,  1889,  Pt  III,  pp.  190-241. 
[nsed   Life,  VII,  p.  279. 
Rept  Ent.  and  Bot  Exp.  Farms  Canada  for  1896,  p.  257  I  1897  >. 

ird  Ann.  Rept.  Ent  Soc.  Ont,  i>.  87,  1002  (1003). 
Bui.  W,  1  > i n .  Ent  I',  S.  Dept  Agric,  p  s^  (1904). 
earbook,  C.  S.  Dept  Agric.  for  1903,  p.  683. 
i  Rept  Ent.  and  Bot  Exp.  Farms  of  Canada  for  1904,  p.  238  (1906). 
*Bul.  93,  Minn.  Agric.  Exp.  sta..  p.  11s   (1906). 
[Clr.  101] 


enemy  to  apples.  The  flies  do  not  spread  rapidly,  and  hence  individ- 
ual orchard-  or  certain  varieties  of  apples  may  suffer  severely,  while 
those  adjoining  may  be  little  injured.  Although  the  pest  was  bred 
from  haws,  in  L867,  in  Illinois,  there  has  been  but  one  record  of  its 
infesting  apples  in  that  State." 

FOOD   PLANTS. 

The  natural  food  of  the  apple  maggot  is  wild  haw  (Crataegus), 
and  probably  several  species  are  infested.  It  was  bred  from  haws 
by  Walsh  in  Illinois,  by  Cook  in  Illinois  and  Wisconsin,  and  by 
Comstock  at  Washington,  D.  C.  Despite  its  supposed  general  occur- 
rence in  the  fruit  of  this  plant,  no  further  records  of  breeding  from 
haws  have  been  found,  and  Professor  Harvey  >tate>  that  it  was  not 
found  in  haws  in  Maine.  During  the  past  three  years  the  Bureau  of 
Entomology  has  collected  or  received  fruit  of  Crataegus  spp.  from 
various  parts  of  the  country,  but  has  not  observed  it  to  be  infested 
with  the  apple  maggot  in  any  instance,  and  it  appears  quite  doubtful 
if  the  distribution  of  the  species  is  as  general  as  is  that  of  its  native 
food  plants. 

The  early  statements  of  the  probable  feeding  of  this  species  on  crab- 
apple  appear  not  to  have  been  based  on  actual  observations,  and 
aside  from  Riley's  record  of  its  occurrence  on  crabs.''  no  definite  data 
have  been  presented  to  show  that  it  infests  this  fruit.  Professor 
Harvey  thought  it  improbable  that  this  fruit  would  be  used,  for  the 
reason  that  it  is  quite  green  and  hard  during  the  period  of  flight  and 
oviposition  of  the  flies.  The  insect  was  found  infesting  plums  and 
late  cherries  in  northern  Michigan,  by  Professor  Cook/  in  1889, 
though  no  additional  records  of  it-  occurrence  in  these  fruits  have 
been  seen. 

Of  apples,  sweet  and  subacid  summer  varieties  are  worst  attacked, 
but  fall  and  winter  sorts  are  also  infested,  including  distinctly  acid 
varieties.  Professor  Harvey  has  prepared  a  list  of  apples  showing 
their  relative  degree  of  infestation  as  observed  by  him  in  Maine 
during  his  careful  study  of  the  apple  maggot.'7 

aCordley.  Orchard  and  Garden,  1889,  p.  192. 
6  Am.  Agric,  1872,  p.  263. 

c  Second  Ann.  Rept.  Mich.  Agric.  Exp.  Sta.,  p.  153. 
d  Loc.  cit. 
[Cir.  101] 


I'orietlea  o)  applet  known  to  be  affected  '"/  Rhagoleti*   (Trypeta)   pomonella.* 


nun 

Bub 

4- 

\l.'\  i  idi 

lutui 

tUtUI 

.1. 

do 

.1.. 
tutus 

- 

Do 

Baldu  1 

Bough 

I       ids  Baldwin 

Badly  Infested 

Do 
N|iuriiigly  1 

Do 
Badl] 

(rated. 

Do. 
Do 

• 

Derby  Pippin 

1 

Badly  Infested. 

Full  Jennrtlng 

A  lit  ll  r 

Do 
Do 

Pall  Pippin 

Sparing 
Do 

Pameuse 

lUtUl 

do 

Km    k 

Badl]  Infested. 

Do 

Golden  Ball 
Golden  Russel 

do 
Vutun 

Autumn     . 

do 

Sparingly  li 
Badly  Intel 

Badl] 

Hlghto     - 

+ 

Hurlbul 

Badly  Infested. 
Sparing 

Iri-ih  Pi   u 

Jewetl  Red 

Summer 

Autumn 

Kins  s-v . .  i 

+ 

Lad]  S 

Maiden  Blush 

Do 
Do 

Mother  . 

Do 

Northern  Spj 

Oldenbu 

lutui 

Sparingly  In 

Badly  Infested 

' 

Pew  aukee  1  ?) 

\  '1 1 11  r : 

Sunn 
\iitim 

- 

Porter 

- 

Sparingly  In  1 

Do. 
Bad!  i 

Primate 

Ramsdell 
Bed  Isl  rai  ban 

Ribston 

Sparingly  Infested, 
ited. 

Kolf,.     . 

Russell. . 

S 
Somerset 

in 

9 

Sops  ol  u     • 

- 

Badly  infested. 

Tetofskl 

+ 

!>•.. 

+ 
+ 

Tompkl 

Sparingly  Inti 

Twentj  ■ 

■■i 

-. 

.In 

'■ 

■ 

Badl] 



Williams                                      „ 

Wtnthrn                                      

Yellow                        

\utumn 

tpr 

Do. 

•  Names  ive  b.»'n   eoneeted   to   agree   with   those  givm   In   "M 

menclature   of   the   Apple,"   by  W.    H.   Regan  Bur.   Plant  Industry,    D 

The  susceptibility  to  injury  of  the  respective  varieties  mentioned, 
as  observed  in  Maine,  would  not  necessarily  be  true  for  other  regions, 
bul  the  li-t  will  serve  to  -how  that  all  classes  of  fruit  arc  subject  to 

[Or.  mil 


attack.  As  a  general  statement,  it  may  be  said  that  the  insect  will  he 
most  destructive  to  summer  and  fall  varieties,  or  to  those  varieties 
which  are  ripe  or  are  approaching  maturity  during  the  period  of 
principal  activity  of  the  flies. 

HOW  THE  INSECT  SPREADS. 

It  is  not  known  whether  the  apple  maggot  has  spread  from  the 
New  England  States,  where  its  injuries  were  first  noticed,  to  the  sev- 
eral localities  where  its  presence  has  been  observed — as  in  Ohio.  Wis- 
consin, Michigan.  North  Carolina,  etc. — or  whether  the  insect,  al- 
ready present  on  haws,  simply  turned  its  attention  to  apples.  The 
former  view,  however,  appears  the  more  probable,  and  its  spread 
would  have  been  readily  brought  about  by  the  introduction  of  in- 
fested apples.  In  regions  where  the  insect  occurs  in  apples,  a  con- 
siderable amount  of  infested  fruit  will  be  barreled,  the  larvae  later 
deserting  the  fruit  and  forming  puparia  on  the  bottom  of  the  barrel. 
In  the  ordinary  course  of  commerce  the  insect  would  thus  be  intro- 
duced into  new  localities,  often  quite  remote.  In  view  of  the  extent 
of  apple  production  in  the  territory  which  has  long  been  infested 
with  this  species  (i.  e..  the  New  England  States),  and  the  consequent 
almost  certain  dissemination  of  the  apple  maggot  to  various  parts  of 
the  country,  it  is  cause  for  much  surprise  that  the  insect  is  not  much 
more  generally  and  widely  established  as  an  apple  pest.  It  is  very 
probable  that  the  insect  has  been  introduced  into  most  of  the  apple- 
growing  regions  in  the  United  States  and  also  into  those  of  Europe 
and  the  Colonies,  but  for  some  reason  has  not  established  itself. 
Thus  the  insect  has  been  frequently  found  in  apples  on  the  markets  in 
Washington,  D.  C..  though  there  is  no  evidence  to  indicate  that  it 
has  become  established  in  orchards  in  that  vicinity. 

When  once  established  in  an  orchard,  its  spread  fortunately  is 
usually  very  slow.  It  may  confine  its  attack  to  a  single  tree,  for  two 
or  three  years,  before  spreading  to  adjacent  trees  of  the  same  or 
other  varieties  equally  subject  to  attack:  and  varieties  seriously  in- 
fested in  one  orchard  may  be  exempt  in  another.  The  slowness  of 
its  spread  from  tree  to  tree  and  from  one  orchard  to  another  has  been 
commented  upon  by  numerous  workers. 

The  flies  in  their  habits  are  exceedingly  local,  apparently  confining 
their  attention  to  the  trees  upon  which  the  previous  generation  devel- 
oped— in  marked  distinction  to  the  spreading  habits  of  many  other 
insects.  This  habit  is  a  very  fortunate  one  for  the  fruit  grower,  and 
is  of  much  practical  importance  in  control,  permitting  great  reduc- 
tion and  possible  extermination  of  the  pests  when  infestation  is  lim- 
ited to  but  a  few  trees,  and  especially  in  localities  but  recently 
invaded. 

[Cir.  101] 


Dl  -i  RIP!  hi\. 

Egg.  The  eggs  oi  the  apple  maggot  are  quite  small,  varying  from 
0.8  i"  0.9  linn,  in  Length  l>y  0.2  to  0.25  nun.  in  width.  Fusiform,  and 
light  yellow  in  color  as  taken  From  the  Fruit.  A  short,  broad  pedicel, 
about  one-twentieth  the  length  of  the  egg,  is  Found  at  the  broader 
end,  which  end  is  darker  and  pitted  with  irregular  hexagonal  cells 
with  raised  lacerated  borders  For  about  one-fourth  the  length  of  the 
egg.     (See  fig.  2,  a.) 

Larva,  The  larva  ifi!_r.  L,  6)  is  Footless,  and  when  lull  grown  is 
From  7  to  S  nun.  Long,  with  a  width  <>t'  From  L.75  to  ■_'  nun.,  yellowish- 


Pio.  2.  —  Rhagoletit   pomonella :  a,  Egg;  '-.  bead  of  larva,  showing  chltlnous  books 
framework  wltbin  tbe  bead,  and  funnel-shaped  spiracle;  •,  caudal  spiracle;  d    oviposi- 
tor, with  which  eneath  ^kin  of  apple,     All  greatly  enlarged.     (6,  c, 
After  Comstock ;  </.  </.  after   Harvey.) 

white  in  color,  at  times  tinged  with  greenish.  The  body  is  composed 
of  I  \  segments,  widest  across  the  ninth,  tenth,  and  eleventh,  and 
sloping  gradually  backward,  and  more  rapidly  toward  the  head  end. 

The  caudal  end  is  truncate,  and  on  the  lower  portion  of  the  anterior 
end  I  first  segment  I  is  a  pair  of  black,  curved,  parallel  hook-,  attached 
to  a  chitinous  framework  within  the  head,  the  hook-  being  used  to 
rasp  the  pulp  in  the  liberation  of  juice  for  food.  A  pair  of  spiracles 
occur-  on  the  dorsal  surface  on  each  side  at  the  juncture  of  the  first 

[fir.  101] 


8 

and  second  segments  (fig.  2,  b)  and  a  pair  on  the  sloping  surface  of 
the  caudal  segment.  The  spiracles  on  the  cephalic  end  have  funnel- 
shaped  mouths,  the  funnel  being  bordered  with  a  double  row  of  about 
20  projections.  The  caudal  spiracles  each  show  3  transverse  slit-like 
openings  and  4  groups  of  bristles.      (See  fig.  2.  c.) 

Pupa. — The  pupa  is  a  small,  barrel-shaped  structure,  pale  yellow- 
ish-brown in  color,  measuring  about  4.2  to  5. -2  mm.  in  length,  with  a 
width  of  from  2  to  2.0  mm.  The  larva  in  pupating  does  not  shed  its 
skin,  but  simply  contracts,  assuming  an  oval  form,  causing  the 
cephalic  spiracles  to  project  in  front  as  tubercles.  Although  the  cau- 
dal end  also  shrinks,  the  spiracles  are  still  visible,  as  are  also  the  body 
segments  of  the  larva.  The  true  pupa  is  formed  within  the  larval 
skin.     (See  fig.  1,  d.) 

Adult. — The  parent  of  the  apple  maggot  is  a  two-winged  fly  (fig. 
1,  a),  somewhat  smaller  than  the  house  fly.  of  a  general  black  color, 
with  yellowish  head  and  legs,  greenish  eyes,  and  dark  feet.  In  the 
male  there  are  3,  and  in  the  female  4  wdiite  bands  across  the  abdomen. 
Across  the  wings  of  both  sexes  are  4  black  band-  as  shown  in  the  fig- 
ure. The  females  are  from  5  to  G  mm.  in  length,  with  a  spread  of 
wings  of  about  12.15  mm.     The  males  are  somewhat  smaller. 

LIFE   HISTORY  AND   HABITS." 

There  is  but  one  generation  of  the  apple  maggot  each  year,  though 
the  occurrence  of  maggots  in  the  fruit  during  the  summer  and 
autumn,  due  to  the  great  irregularity  in  time  of  appearance  of  the 
flies,  is  calculated  to  mislead  those  not  familiar  with  the  insect's  life 
history.  The  time  and  appearance  of  the  adults  is  thought  to  be 
influenced  by  the  date  of  the  ripening  of  the  fruit  which  they  in- 
fested the  previous  season,  though  this  supposition  has  not  been 
established.  During  an  ordinary  season  in  Maine,  the  flies  will 
begin  to  appear  and  will  be  ovipositing  about  July  1.  and  earlier  in 
the  States  to  the  south.  By  the  middle  of  July,  in  Rhode  Island, 
during  an  average  season,  as  stated  by  Profs.  F.  W.  Card  and  A.  E. 
Stene,  early  varieties  subject  to  attack  will  show  many  of  the  egg 
punctures  of  the  females. 

Flies  have  lived  in  confinement  for  three  weeks,  and  out  of  doors 
the  period  is  doubtless  somewhat  longer.  The  female  makes  punc- 
tures through  the  skin  of  the  apple  by  means  of  her  sharp  ovipositor 
(fig.  2,  d),  inserting  the  eggs  singly  into  the  flesh  in  a  vertical  posi- 
tion. Oviposition  may  occur  on  any  part  of  the  fruit,  though  mostly 
on  the  side  and  especially  on  the  paler  portions,  where  the  apple  has 

"The  apple  maggot  was  carefully  investigated  in  Maine  by  the  late  Professor 
Harvey,  and  his  Report  (1.  c.)  has  heeu  largely  the  basis  of  the  present  article. 

[Cir.  101] 


been  protected  from  the  sun  \<\  the  foliage.  An  individual  female 
is  capable  of  producing  from  300  to  100  egg  .  egg  laying  continuing 
throughout  her  life.  About  one-half  minute  is  occupied  in  the  act 
of  depositing  ;i  single  egg,  and  the  characteristic  brownish  speck  l<Ti 
by  the  ovipositor  can,  ■  i j >« * 1 1  clo  e  examination,  be  detected  bj  the  un- 
aided eye,  and  resembles  the  brownish  rustj  spots  occurring  normally 
on  some  varieties.  These  egg  punctures  tnaj  be  best  observed,  how 
ever,  with  a  hand  lens,  and  are  then  seen  i"  be  oblong  or  circular 
hole-,  with  i  li«'  surrounding  border  brownish  ;in<l  somewhat  shrunken. 
In  four  nr  five  days,  under  favorable  conditions,  the  egg  hatches  and 
the  minute  footless  maggol  begins  t"  feed  on  the  pulp  of  the  fruit. 
Although  the  larva  is  without  tine  opposable  jaws,  it  is  provided 
with  two  hook-  mi  tlic  head  above  the  mouth  by  which  the  pulp  is 
rasped  loose,  the  larva  drawing  into  the  mouth  the  juices  thus  lib- 
erated.  The  pulp  which  is  not  eaten  soon  turn-  brown  and  renders 
the  burrows  through  the  flesh  more  readily  visible.  The  larva,  in 
it-  feeding,  channels  here  and  there  through  the  flesh,  sometimes 
burrowing  for  ;i  distance  jusl  under  the  skin,  the  brownish  trail  in 
light-skinned  varieties  appearing  as  ;i  linear  bruise. 

The  rate  of  development  of  the  larvae  conforms  t<i  that  of  the  fruit, 
and  the  larvae  do  not  mature  until  the  fruit  i-  ripe.  Early  appearing 
flies  attack  the  summer  varieties,  and  those  appearing  later  infest 

fall  and  winter  sorts.  Their  development  is  cheeked  by  cold,  and 
they  are  apparently  aide  to  exisl  for  a  considerable  time  ill  a  prac- 
tically stationary  condition  until  the  maturity  of  the  fruit  permit-  of 
their  further  growth  to  maturity. 

Apples  at  gathering  time  may  -how  no  exterior  indication-  of  in- 
festation, yet  when  cut  open  will  he  found  thoroughly  burrowed  and 
honeycombed  by  the  larva;;  or  the  apparently  sound  mature  fruit  may 
he  -o  infested  with  the  small,  inconspicuous  larvae  and  eggs  thai  it 
may  be  soon  destroyed  after  storing.  The  work  of  a  single  mascot 
will  injure  the  value  of  the  fruit,  though  a  do/en  or  more  may  often 
he  present.  Under  favorable  condition-  of  temperature  and  in  ripen- 
ing fruit,  the  maggots  will  become  full  grown  in  four  or  five  week-. 
The  larvae  mature  a-  the  fruit  i-  ripe,  and  leave  this  after  it  ha-  fallen 
to  the  ground,  as  no  exit  hole-  have  been  noticed  in  fruit  on  the  tree-. 
In  deserting  the  fruit  a  hole  i-  made  through  the  -kin  and  the  larva 
burrows  an  inch  or  less  below  the  surface  of  the  soil,  or  on  -oil  land 
probably  pupates  around  the  root-  of  the  grass;  or  sometimes  the 
pupal  stage  i-  entered  on  the  surface  of  the  ground  under  the  de- 
cayed fruit.  In  fruit  in  barrels,  in  storehouses,  etc,  the  larva; 
pupate  on  the  bottom  of  the  receptacle,  ami  the  puparia  are  often 
very  numerous  in  such  place-.  The  insect  remain-  in  the  pupal  stage 
[Ctr.  101 J 


10 

until  the   following  summer,  the  adult  fly  appearing  early  or  late, 
depending  apparently  on  whether  the  larvae  infested  summer,  fall,  or 

winter  fruit. 

INSECTS    WHICH    MAY    UK    MISTAKEN    FOB   THE   APPLE    MAGGOT. 

There  will  often  be  found  in  apple-  partly  or  wholly  decayed,  as 
from  the  work  of  the  apple  maggot  or  other  causes,  larvae  which 
might  very  readily  be  mistaken  for  those  of  the  species  under  consid- 
eration. Principally  the  larvae  of  two  kinds  of  flies  will  thus  be 
found,  namely,  the  vine-loving  pomace  fly  {DroHopluhi  ampelophUa 
Loew) — a  small  clear-winged,  red-eyed  fly — and  the  pretty  pomace 
fly  (Drosophila  amcena  Loew),  similar  to  the  former,  but  with  black 
spots  on  the  wings.  These  insects  are  of  interest  as  likely  to  be  mis- 
taken for  the  apple  maggot  and  hence  the  cause  of  needless  alarm. 
They  are  of  little  economic  importance,  though  undoubtedly  hasten- 
ing the  decay  of  fruits. 

PREVENTIVE   MEASURES. 

The  apple  maggot  has  proved  to  be  an  unusually  troublesome  in- 
sect to  combat  successfully.  The  eggs  are  deposited  beneath  the  skin 
of  the  fruit,  within  which  also  the  larva  feeds  until  full  grown.  The 
pupal  stage  is  passed  just  under  the  soil,  or  around  the  roots  of  gra- 
in sod  land,  and  the  flies  do  not  feed  in  a  way  to  permit  of  their 
destruction.  Spraying  with  arsenicals.  so  effective  against  the  codling 
moth  or  apple  worm,  is  for  this  pest  quite  useless. 

The  insect,  however,  may  be  attacked  in  two  important  ways.  As 
stated,  the  larva?  do  not  leave  the  fruit  until  the  latter  has  ripened 
and  fallen  to  the  ground.  The  prompt  gathering  and  destruction  of 
the  windfalls,  before  they  are  deserted  by  the  maggots,  would  serve 
to  keep  the  insects  greatly  reduced,  amounting  to  practical  extermina- 
tion if  thoroughly  carried  out.  This  practice  has  long  been  recom- 
mended by  entomologists,  and  comprises  the  most  effective  measure 
of  controlling  the  pest  at  present  known.  Greatest  benefit  will  come 
from  the  practice  when  carried  out  uniformly  by  the  orchardists  of  a 
community.  Allowing  the  wormy  fruit  to  decay  on  the  ground  is 
most  favorable  to  multiplication  of  the  apple  maggot.  Orchardists 
having  this  pest  to  contend  with  should  arrange  to  destroy  the  in- 
fested fruit  promptly  after  it  falls,  and  this  may  be  accomplished  in 
whatever  way  is  most  practicable  under  individual  conditions. 

Picking  up  the  fruit  by  hand  will  often  prove  feasible  and  can  be 
done  by  children,  but  great  care  is  necessary  that  the  work  be  done 
thoroughly.  The  gatherings  should  be  made  daily  if  possible,  or  at 
least  every  two  or  three  days.     The  fruit  may  be  fed  to  stock,  taking 

[Cir.  101] 


11 

care  thai   ;in\   excess  n<>i   a!   the   moment   n led  be    tor  'I   in   tight 

boxes  or  receptacles  bo  that  any  larva?  deserting  the  fruit  will  be 
forced  to  pupate  on  1 1 1 •  -  bottom  of  the  container,  where  later  they  may 
he  destroyed!  When  the  drop  fruit  is  not  needed  for  the  stock,  it 
may  be  simplj  thrown  into  a  hole  <>r  hole-  here  and  there  in  1 1  * •  - 
orchard,  i<>  be  finally  covered  \\  iili  2  or  '■'>  feet  of  earth  in  1 1  • « -  late  fall 
after  frosts  have  occurred,  i"  prevent  the  «--<-:  1 1 f  flies  the  following 

i  on.  The  worh  of  gathering  need  not  be  begun  until  1 1 » *  -  firsl  ripe 
windfalls  of  the  early  varieties  are  found,  but  should  1"'  kept  up  from 
thi>  time  until  all  the  fruit  has  been  harvested. 

Orchards  may  often  be  pastured  with  sheep,  hogs,  or  cattle,  in  a 
way  i"  insure  the  destruction  of  the  windfalls,  and  this  practice  is 
recommended  as  the  cheapest  and  most  satisfactory  method  i>t'  deal- 
ing with  the  apple-maggot  problem.  Orchards  may  be  permanently 
pastured  or  the  stock  turned  in  daily  in  sufficient  numbers  and  ;it 
times  to  accomplish  the  desired  consumption  of  the  fallen  fruit.  This 
practice  will  be  especially  useful  in  commercial  orchards,  and,  where 
infestation  from  adjacent  orchards  i-  not  great,  will  insure  practically 

clean    fruit. 

Plowing  and  cultivation  of  orchards  would  appear  to  i>e  a  useful 
practice  in  the  control  <d'  this  pest,  and  these  methods  have  been 
more  or  less  recommended  for  some  years.  Careful  experiments  in 
Rhode  [sland  on  the  value  of  such  work  have  recently  been  reported 
by  Professors  Card  and  Stene."  Puparia  of  apple  maggots  were 
placed  at  different  depth-  in  the  soil,  ranging  from  1  to  ,;  inches,  to 
approximate  condition-  resulting  from  plow  ing  to  bury  the  pupa?,  but 
this  was  found  to  have  little  effect  in  preventing  the  escape  of  flies, 
and  the  conclusion  was  reached  that  spring  plowing  of  orchards  to 
turn  under  the  pupa'  was  valueless,  under  the  soil  condition-  which 
there  obtained. 

It  is  thought,  however,  that  frequent  tillage  of  the  orchard  in  early 
summer  may  be  unfavorable  to  the  development  of  the  pupae  to 
flies,  ami  experiments  made  in  1904  by  Messrs.  Card  and  M.  A. 
Blake1  with  pupa?  placed  in  boxes  in  which  the  soil  was  frequently 
stirred,  resulted  apparently  in  their  complete  destruction.  More  ex- 
tended and  conclusive  experiments  along  these  lines  are  urgently 
needed.  Aside  from  its  possible  value  in  destroying  the  apple  maggot, 
frequent  tillage  of  orchard-  in  late  spring  and  early  summer  is  de- 
sirable, especially  for  young  tree-,  as  favoring  a  better  tree  and  fruit 
development. 

Seventeenth  Ann.  Kept  EL  I.  Agr.  Exp.  Sta„  Pari  EI,  p.  191  (1904). 

ghteentn  Ann.  Rept.  EL  I.  Agr.  ESxp.  Sta.,  Pari  EI,  p.  197  (1906). 
[Clr.  101] 


12 

3  1262  09216  5447 

Much  infested  fruit  goes  to  market,  or  is  stored  at  home  for  future 
consumption.  The  refuse  from  such  fruit  should  always  be  de- 
stroyed, and  the  hands  and  boxes  in  which  the  maggots  have  pupated 
upon  leaving  the  fruit  should  he  treated  in  such  a  way  as  to  insure 
the  destruction  of  the  pupae.  The  (loor  of  storerooms  should  also  be 
carefully  swept,  and  the  sweepings  collected  and  burned. 
Approved : 

James  Wilson, 

Secretary  of  Agriculture. 

Washington,  I).  ('..  March  27,  1008. 

[Cir.  101] 

o 


